The plains pocket mouse is a resident of Colorado’s eastern grasslands. Open occurrence databases hold 249 records for it, nearly all drawn from museum specimens and field-trapping surveys rather than photographs, because this tiny, strictly nocturnal burrower is almost never seen above ground in daylight.
A shortgrass sand specialist
This pocket mouse favors loose, sandy soils it can dig through, and its records concentrate in the eastern plains counties, Washington, Weld, Yuma, and Logan, out on the shortgrass prairie and the sandhills of the South Platte country. It carries fur-lined external cheek pouches, the pockets of its name, which it uses to haul seeds back to underground caches rather than eat them where they fall.
Underground for the cold half of the year
The occurrence record all but stops from late autumn into early spring, and that gap is real, not merely a lull in fieldwork. Plains pocket mice do not truly hibernate, but they withdraw into their burrows for the winter, living off stored seed and dropping into torpor to ride out the cold. Activity, and with it the records, resumes as the ground warms and the animals return to the surface at night.
Status in Colorado
Native and secure, ranked S5 by NatureServe. Easily overlooked, it is nonetheless a widespread member of the plains rodent community and an important mover of seed and prey animal across sandy grassland.



